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Shell and draft (or a different approach) for internal support for 3D print?
Deposition printing doesn't deal well with overhangs, so there are a several different approaches to supporting overhangs sufficiently to be printed.
Most slicing tools include semiautomatic generation of fill grids or breakaway supports.
Some specialized tools are partly or all about support generation (Meshmixer shown):
And some folks just design their part so there's no unsupported overhang -- this is the approach I'm wanting to find a recipe to easily accomplish.
(I've built a test document if anybody wants to play with this: https://cad.onshape.com/documents/f76d5c67855346c2aef32402/w/5f5fb53d0c6842ca93657284.)
Let's say this is my part; simple block with filletted top edges.
If I were making this for molding, I'd just shell it (maybe add some screw bosses and supports) then draft it.
But that big roof is really hard for a deposition printer to manage.
(For anybody who doesn't have direct experience, UT has a nice writeup and example pictures of things going badly here; scroll down to the "Limits of the 3D Printers" section.)
What I'm looking for is a simple recipe (just as, if I had molding in mind, shell-then-draft is pretty simple) for building support into the part. In another tab of my doc is this...
...which I created by setting the thickest shell that still left any cavity at all, then experimenting with high draft angles until I got what looked like enough support.
That process, however, is ugly and iterative, and once the part reaches real-world complexity, unworkable:
Without going all the way to a post-process with another purpose-specific tool (like Meshmixer) is there a simpler approach? Some loft approach that's not obvious to me, etc?